Flow Field Imaging for Quantitative Cycle Resolved Velocity Measurements in a Model Engine

This paper describes the apparatus and techniques used to record and analyze the images of seed particle trajectories in reciprocating motored engines. Frequency modulated strobing of a CW laser light sheet illuminating the particles produces a series of tracks that are detected by an intensified TV camera, recorded on videotape and analyzed using an image processing system. A data interpolation scheme to calculate velocity vectors in order to compare velocity fields in different cycles is used and cycle resolved velocity fields are presented.